Constraints are rules that decide what data can enter the database tables. SQL server has six types of constraints and we will explore all these here with suitable examples. The constraints that we are going to explore are listed below: Primary Key Foreign Key Not Null Unique Default Check
Articles on SQL, TSQL and Management Studio. You can download Microsoft supplied sample database here: https://drive.google.com/file/d/0B8H2WLrOYbPxcy13RG9JNUpRRHM/edit?usp=sharing
We all know that to insert data into SQL server database we use the Insert statement. This article explains inserting data into the database table using various techniques available. First, we will start with normal insert statements. Then we will go ahead with inserting data from existing tables in the SQL Server Database.
“Table Joins” are useful for bringing data together from different tables based on their database relations. First, we will see how the join operates between tables. Then we will test the Order of Execution when Join and where condition both lies. Finally, we will move our exploration to Importance of the Join order. It is a good idea to know about database table relationships before reading this article.
1. Introduction to Grouping & Sorting In this article, we will explore group and sort the result of an SQL query. The Order By informs SQL engine to arrange the query output in ascending or descending order. To put it differently, the Order By will sort the output query result on a specific column or columns. We … Continue reading
RDBMS Database supports the relationship between tables. One can do this by linking the columns. This article shows how to modal the relationships One-to-One, One-to-Many and Many-To-Many with examples. The relationship One-to-Many can also be seen as Many-to-One.